The present invention relates generally to railroad electropneumatic brake equipment and more specifically to a cable system for an electropneumatic brake unit.
The availability of computer controlled railroad brake equipment includes the CCB equipment available from New York Air Brake Corporation. The CCB locomotive brake control equipment is described in U.S. Pat. No. 5,172,316 and a portion of which is illustrated in FIG. 1. The numbers used throughout this application correspond to that used in this patent for sake of clarity and consistency.
With the addition of electropneumatic braking and other electric subsections, there has been a proliferation of new on-board locomotive subsystems. Since the interconnection of these various subsystems have been added one by one, it has increased the complexity of their interconnection and their weight. For example, the complexity of the brake control portion or pneumatic control unit 62 of the CCB is illustrated in FIG. 1. The manifold is complex and wiring from the microcomputer 56 must be connected to each of the individual electrical valves and transducers. Further complexity is added in that electric valves and transducers do not have standard electrical connectors and therefore each of the wires must include a termination or connector which would mate with the respective connector on the transducer or valves. The wires and bundles must be securely positioned on and between the various electropneumatic and pneumatic valves and electrical transducers.
There are thirty-four line replaceable units mounted to this manifold. Since the locomotive cannot carry thirty-four of the individual components, the whole locomotive must be taken into a shop for repair. The complete brake control portion 62 can be removed and a new one inserted. This takes a substantial amount of time because of the number of wires and interconnections for the electrical components. The brake control portion 62 would then have to be tested and the individual parts replaced.
To address these problems, the present invention is a cable system including device connectors connected to electropneumatic valves and electrical sensors at predetermined positions along a path on a common manifold and a wiring harness having a length sufficient to transverse the path. The wiring harness includes a plurality of insulated wires in a common sheath and selectively connected to harness connectors which are mounted at predetermined positions to the harness and mate with a corresponding device connector. The path is a closed loop and the wiring harness forms a corresponding closed loop. The majority of the wires in the wiring harness form the corresponding closed loop.
The mounting of the harness connectors to the harness includes a water-tight seal and preferably is a molded connection. The sheath is discontinuous at the mounting of the harness connectors to the harness to expose the wires. The molded mounting encompasses the exposed wires, the ends of the sheath at the discontinuity and a portion of the harness connector. Each wire in the harness is connected to more than one of the harness connectors. Each harness connector includes a pin for each wire selectively connected thereto. Corresponding pins of the harness connectors are interconnected one to another by continuous segment of wire of the harness. A pair of wire segments are connected to each of the selected pins.
Preferably, the electropneumatic valves and electrical sensors, as well as other electronic devices, are grouped into a module mounted to the manifold. Each module includes one device connector for connecting all of the electropneumatic valves, electrical sensors and other electrical components of the module to the harness. A junction box, also provided on the manifold, has a plurality of box connectors interconnected at the junction box. One of the box connectors is positioned along the path and the wiring harness includes a harness connector positioned to mate with the box connector positioned along the path. Each of the modules includes a transceiver connected to its device connector. The junction box includes an electrical power source connected to the box connector along said path. Thus, the wiring harness interconnects the module for communication as well as providing a power source.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.